There is also a Wonder Weeks book which explains it all in much more detail. The app will only give you a rough guide as to what skills your baby is trying to master during the leap period and what new skills they will have by the end of the leap and roughly when these leaps will occur. The book will go into more detail and explain what types of behaviours you might expect to see during the period of the Mental Development leap and what exactly is going on in their brain. It will also give you tips on what you can do to help settle them during the period, as usually babies are quite unsettled and go through what they call 'a stormy period' during this time. They can last a week or two usually, some are even three weeks.
This all is, however a guide like everything else. As my paediatrician says, yes all babies go through the same milestones and develop the same skills but they don't usually happen at the same time for every baby and they don't develop the same skills during the same leaps either. The book does explain this though and judging by what I've seen on this forum all of the leaps tend to happen at roughly the same time the book and app suggest.
My son has gone through each leap 1 week early and he was born early so according to the book he should go through the leap late if anything but the book is a guide and all babies are different.
Also my baby picked up some of the mentioned skills during the first leap but he also picked up some that they mention for the second leap.
My friend's baby picked up some skills my son didn't such as making sounds and my son picked up some skills hers didn't such as lifting his head without support.
Eventually though babies learn all of the skills when they are ready.
So basically it's a guide to know when your baby could be extremely grumpy and needy for a week or two, (by the way some babies cope with this development just fine and their parents don't even notice the leaps).
It helps make it that much easier knowing why they are grumpy and what they will be able to do when they are not grumpy anymore.
I hope this helps.
The book is quite a good read and it's good to know how much their little brains are going through and better understand why babies are the way they are.

In reply to Purple1110

18/11/16

There is also a Wonder Weeks book which explains it all in much more detail. The app will only give you a rough guide as to what skills your baby is trying to master during the leap period and what new skills they will have by the end of the leap and roughly when these leaps will occur. The book will go into more detail and explain what types of behaviours you might expect to see during the period of the Mental Development leap and what exactly is going on in their brain. It will also give you tips on what you can do to help settle them during the period, as usually babies are quite unsettled and go through what they call 'a stormy period' during this time. They can last a week or two usually, some are even three weeks.
This all is, however a guide like everything else. As my paediatrician says, yes all babies go through the same milestones and develop the same skills but they don't usually happen at the same time for every baby and they don't develop the same skills during the same leaps either. The book does explain this though and judging by what I've seen on this forum all of the leaps tend to happen at roughly the same time the book and app suggest.
My son has gone through each leap 1 week early and he was born early so according to the book he should go through the leap late if anything but the book is a guide and all babies are different.
Also my baby picked up some of the mentioned skills during the first leap but he also picked up some that they mention for the second leap.
My friend's baby picked up some skills my son didn't such as making sounds and my son picked up some skills hers didn't such as lifting his head without support.
Eventually though babies learn all of the skills when they are ready.
So basically it's a guide to know when your baby could be extremely grumpy and needy for a week or two, (by the way some babies cope with this development just fine and their parents don't even notice the leaps).
It helps make it that much easier knowing why they are grumpy and what they will be able to do when they are not grumpy anymore.
I hope this helps.
The book is quite a good read and it's good to know how much their little brains are going through and better understand why babies are the way they are.

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